反应详情

175 g (0.71 mol) of 1-(4-chlorophenoxy)-3,3-dimethyl-4-fluoro-butan-2-one were dissolved in 500 ml of methylene chloride, and 114 g (0.71 mol) of bromine were added dropwise at 20° to 30° C., while stirring and cooling. The mixture was subsequently stirred at 20° C. for 2 hours, 200 ml of water were added carefully and the methylene chloride phase was washed several times with ice-water and dried over sodium sulphate. After distilling off the solvent in vacuo, the residue was recrystallized from cyclohexane. 180 g (78% of theory) of 1-bromo-1-(4-chlorophenoxy)-3,3-dimethyl-4-fluoro-butan-2-one of melting point 73°-75° C. were obtained. ##STR26##

1. temperaturecooling
2. stirringThe mixture was subsequently stirred at 20° C. for 2 hours
3. washthe methylene chloride phase was washed several times with ice-water
4. dry with materialdried over sodium sulphate
5. distillationAfter distilling off the solvent in vacuo
6. customthe residue was recrystallized from cyclohexane